Montgomery Clift (Prof. James Bower)
Hardy Kruger (Counselor Peter Heinzman)
Macha Meril (Frieda Hoffman)
Roddy McDowall (C.I.A. Agent Adam)
David Opatoshu (Orlovsky)
Jean-Luc Godard (Orlovsky's Friend)
Uta Levka
Curd Jürgens
Christine Delaroche (Ingrid)
Hannes Messemer (Dr. Saltzer)
Karl Lieffen (The Major)